Wednesday, September 24, 2008

The Good, the Bad, and the Ugly: Biological Control at the Conservatory

The horticulture staff faces a number of challenges when it comes to keeping the conservatory's plant collections looking their best. One of the most constant is dealing with pest insects attacking the collections. Having so many plants in contained environments, their density and year-round growing seasons create a great opportunity for pest insects to make themselves at home. At the conservatory, we try to choose the most effective and people-friendly (we are open to the public every day) options. The most interesting of which is biological control, or the use of one organism to control the population of another (undesirable) organism. Sure, there are sprays to kill bugs, or even the simple removal of a pest. But introducing predators and parasites to kill pest populations is far more exciting!

Since we grow plants year-round and in such high density, they are much more suceptible to pest attacks. If one plant harbors an insect, chances are the plants nearby eventually will , too. There is no freezing or dormant season,like there is outside, either. We regularly monitor our plant collections, looking for evidence of the unwelcome insects feeding on our plants--this could be something as obvious as spots on leaves or flowers, or something as minute as the perpetrators themselves. We receive shipments of "good" bugs, as often as weekly, and release them in areas where we know we have an issue. The beneficial organisms are often specific to certain pest insects; they are usually predators or parasites that prefer certain species. We can order them from a catalog and recieve them within a week.

Be sure to look around the conservatory and you may see some of our good bugs in action--sometimes there are ladybugs wandering around looking for an aphid snack. This may sound awfully gory, but there is a satisfaction to knowing that the bugs responsible for ruining a stunning flower, or destryong the leaves of a specimen tree, are being devoured by another insect. Or maybe I am just a vindictive gardener....

Wednesday, September 17, 2008

Reusing Container Plants

Every year on the zoo, we have about 35 planted containers on display around the Visitor Center and Main Zoo Building. This season there were a variety of plants including sumac, purple fountain grass, Japanese blood grass, gazanias, and sweet potato vine planted in the containers. For the first time, we decided to grow a perennial shrub in our containers to later be planted on zoo grounds. The sumac was planted in the containers as a 1-3 gallon nursery sized plant. Throughout the season they have flourished and are now about 4 feet tall.

Now this week we have taken the zoo pots off of display and are harvesting the sumac to be planted alongside the lion exhibit. Sumac is a great plant choice for this area because the lions like the shelter the plants provide, but visitors will still be able to peer through the plants to catch glimses of the lions. We are in a race against the clock as to when the plumbers will shut off our water, so it is essential that we get them planted while we still have access to water to get them watered in. It's amazing how quickly the growing season winds down.

Wednesday, September 10, 2008

Environmental Maintenance in the Fern Room

Like all of the Conservatory's display rooms and greenhouses, the Fern Room maintains specific environmental conditions. These conditions help create a healthy atmosphere for the fern collection, as well as an interesting and distictive experience for our visitors. The conservatory's fern collection consists of over 100 species of ferns and fern allies. Most of our ferns are native to Asia, New Zealand, Australia, and Hawaii--places with climates that are very different from the hot, hot summers and frigid winters here in Minnesota. To create the best display for these plants, we rely on a computer system to monitor and maintain environmental standards in the room. The space is cooled in the summer by motorized vents, fans, and a fog system; it is heated in winter with radiant heat from a system of hot water pipes. The ferns not only require specific temperature ranges, but also higher levels of humidity. When the humidity falls below a specified range, mist nozzles automatically turn on to fill the air with additional moisture. Without these controls, it would be impossible for us to display such a large collection of these types of ferns.

We have reached a point where the heat and mist systems we rely on so heavily are in need of maintenance before the cold days of fall and winter. Between the 8th and 18th of September, we will be repairing our heat system and replacing mist nozzles to ensure peak performance for the upcoming winter. While this will temporarily impact access to the room for us and visitors, it will help us be sure we can maintain the best possible conditions for our beautiful collection. We are working daily to keep the plants out of harm's way as the scaffolds go in, allowing workers to complete the installation with minimal impact to the overall display.

The current Fern Room has been open since 2005, replacing a much smaller and less accessable space. Since the opening of this room, we have been able to expand our collection to include larger species, like the towering tree ferns, and some more unique plants, like the staghorn ferns growing up the rock wall.

Thursday, September 4, 2008

Como Park Zoo and Conservatory at the Fair

Como Park Zoo and Conservatory had a special booth at the fair this year. The theme this year for the exhibit was "Orchids on a Stick." Many brightly colored orchids were featured. There were over 350 plants to be judged overall contributed by variety of sources. Como Park Zoo and Conservatory won first place in the category of less then 30 plants and also the special prize of Best Exhibit overall. They also won another special ribbon for "Best Specimen" plant which was awarded to Coilostylis ciliaris . Overall Como Park Zoo and Conservatory won 13 First place, 7 second place and 5 third place ribbons as well as the two special ribbons.

Also during the week the lights will be left on in the Marjorie McNeely Conservatory. Stop by during the evening to get some great pictures of the lighted dome.